Plinko.java

import java.util.Scanner;

class Plinko 
{
    public static final int SINGLE_DISC = 1;
    public static final int MULTI_DISC = 2;
    public static final int TERMINATE = 3;

    public static final int[] VALUES = {1, 3, 2, 0, 5, 0, 2, 3, 1};
    public static int[] slotPoints =   {0, 0, 0, 0, 0, 0, 0, 0, 0};
    public static int[] slotHits =     {0, 0, 0, 0, 0, 0, 0, 0, 0};

    public static int mode = -1;
    public static int startingPosition = -1;
    public static int discPosition = -1;
    public static int numDiscs = 1;
    public static int finalPoints = 0;
    public static int finalPosition=-1;

    public static void main(String[] args) 
    {
        Scanner scan;
        while(true) 
        {
            //Loop to select mode.
            //This loop is infinite until the user selects the "Quit" option (3)
            Boolean isMultiDisc = false;
            scan = new Scanner(System.in);
            printModeStatement();
            if(scan.hasNextInt()) 
            {
                mode = scan.nextInt();
                if(mode == SINGLE_DISC) 
                {
                    isMultiDisc = false;
                    numDiscs=1;
                }
                else if(mode == MULTI_DISC) 
                {
                    isMultiDisc = true;
                }
                else if(mode == TERMINATE) {
                    System.out.println("Goodbye");
                    break;
                } 
                else 
                {
                    continue;
                }
            }

            collectSettings(isMultiDisc);
            runPlinko(isMultiDisc);
        }
    }

    public static void runPlinko(Boolean isMultiDisc)
    {
        for (int dropNumber=0; dropNumber<numDiscs; dropNumber++)
        {
            discPosition = startingPosition;
            for(int i=0; i<12; i++)
            {
                if (!isMultiDisc)
                {
                    
                    if (isEven(i))
                    {
                        printEvenRow(discPosition);
                    } 
                    else 
                    {
                        printOddRow(discPosition);
                    }

                
                }
                int moveRightChance = (int) (Math.random()*2);
                if (discPosition==0) discPosition++;
                else if (discPosition==16) discPosition--;
                else if (moveRightChance==1) discPosition++;
                else if (moveRightChance==0) discPosition--;
            }
            finalPosition = discPosition/2;
            
            slotHits[finalPosition]++;
            slotPoints[finalPosition] += VALUES[finalPosition];
            finalPoints+=VALUES[finalPosition];
        }
            System.out.print("\n");
            if (isMultiDisc)
            {
                for(int i=0; i<=8; i++)
                {
                    System.out.println("Position "+i+"\tHits: "+slotHits[i]+"       \tPoints: "+slotPoints[i]);
                }
                System.out.println("Final points: "+finalPoints);
            }
            else
            {
                System.out.println("Your disk landed in position "+finalPosition+" and you won "+VALUES[finalPosition]+" points!");
            }
            System.out.print("\n");
            clearResults();
    }

    public static void printOddRow(int discPosition) 
    {
        //Print the visualization of an odd numbered row with the disc in the provided position.
        System.out.print("\t");
        for(int i=0; i<=16; i++)
        {
            if (i==discPosition) System.out.print("O");

            else if(isEven(i)) System.out.print(".");

            else System.out.print(" ");
        }
        System.out.print("\n");
        
    }

    public static void printEvenRow(int discPosition)
    {
        //Print the visualization of an even numbered row with the disc in the provided position.
        System.out.print("\t");
        for(int i=0; i<=16; i++)
        {
            if (i==discPosition) System.out.print("O");

            else if(isEven(i)) System.out.print(" ");

            else System.out.print(".");
        }
        System.out.print("\n");
        
    }

    public static void collectSettings(Boolean isMultiDisc)
    {
        Scanner scan;
        Boolean isValidInput = false;
        while(!isValidInput) 
        {
            scan = new Scanner(System.in);
            System.out.print("Pick a slot to drop the disc(s) (0-8): ");
            if(scan.hasNextInt())
            {
                startingPosition = scan.nextInt() * 2;
                if(0 <= startingPosition && startingPosition <= 16) 
                {
                    isValidInput = true;
                }
            }
        }

        //How many discs will be dropped?
        isValidInput = false;
        if(isMultiDisc) 
        {
            while(!isValidInput) 
            {
                scan = new Scanner(System.in);
                System.out.print("Enter # of discs to drop: ");
                if(scan.hasNextInt())
                {
                    numDiscs = scan.nextInt();
                    if(numDiscs > 0) 
                    {
                        isValidInput = true;
                    }
                }
            }
        }
    }

    public static Boolean isEven(int x) {
        return x % 2 == 0;
    }

    public static void printModeStatement() 
    {
        System.out.print(
            "Select a mode:\n"
            + "\t(1) Single disc\n"
            + "\t(2) Multiple discs\n"
            + "\t(3) Quit\n"
        );
    }


    public static void clearResults()
    {
        finalPoints=0;
        for(int i=0; i<=8; i++)
        {
            slotHits[i]=0;
            slotPoints[i]=0;
        }
    }
}